Apparatus for sealing containers



Aug. 24, 1948. T. F. cAss, JR, ETAL APPARATUS FUR SEALING CONTAINERS 8Sheets-Sheet 1 Filed April 23, 1943 E'anc'za (1/. Lanzgan f IINVVENTORSI I T/omaaf CZzsax/r? Dongle: Kirk and m r a L rva r am am,\

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Aug. 24, 1948. 'r. F. CASS, JR., ETAL 2,447,997 APPARATUS FORYSEALINGCONTAINERS Filed April 23, 1943 I a Sheets-Sheet 2 T. F. CASS, JR.,EI'AL APPARATUS FOR SEALING CONTAINERS Aug. 24, 1948.

s Sheets-Sheet 3 Filed April 23, 1943 INVENTORS .Tfiams F C 62515, J?.DozgZcz; Er k and Aug-24, 1948. T. F.- CASS-JR. EIAL ,997-

. APPARATUS FOR SEALING CONTAINERS 8 Sheets- Sheet .4

Filed April 25, 1943 Aug. 24, 1948.

Filed April 2:5, 194s T. F. CASS, JR, ETAL APPARATUS FOR SEALINGCONTAINERS 8 Sheets-Sheet 5 21167 1&7 "\5' T/wznaa F Cass, Jr Jazzy/asKirk and fian'c'zls' Z'd Larzgtzn T. F. CASS, JR, ETAL v APPARATUS FORSEALING- CONTAINERS 8 Sheets-Sheet 6 Filed April 23, 19475 fiuerpiansf/Zrns F Caz-51$; J. flaz glas Kirk and ganc'ia Lara T. F. cAss, JR,ETAYL APPARATUS FOR mung conmnms Aug. 24, 1948.

a Sheets-sheaf 7 Filed April 23, 1943 fizvezzt a sw fomas F Cass, J.

aid z 'garz,

flaz ylw Kiri Francis ZZZ .Zan 1 87% B- 4, 1948. T. F. cAss, JR, ETAL2,447,997 APPARATUS'FOR SEALING conmnnns Filed April 25, 1943 f sSheets- Sheet 8 fiat/67222715:

T Aomasf Caz-51 @ozasglas Kirk and fiancis ZZZ Lani Patented Aug. 241948 UNITED STATES ATENT OFFICE 447,997 1 i eiiRAiiIs Foe saeLnut';rcom-rinses" Thomas F; Cass; :liz, Wayne, and Douglas K'ii-k, I

Chicago; I11., and Francis WA Lanigan, Lincoln Mass, a'ssignors, bydirect and 'm'esne assignments, to Qontainer Corporation of America,Chicago, 111., a corporationof Delaware appiicatiea sprites,1943,'seria1-Nb; 484,306

7 Claims.

This invention relates to apparatus for sea-1 ing containers and moreparticularly to cont-inn ousautomatic machines especially adapted toreceive paper board cartons whichghave been-filled with a desiredproduct and to'eifect'closing and sealing of the top flaps thereof.

While a number of types of machines for' this purpose, generallyreferred toas-top=sealing'machines, are available'andmany others havebeen proposed, they are generally notadaptedtdhe used in connection withpackaging processinvolving heat-sealing of the top a'rton fiapsgor theyare characterized"byrelatively slow intermittent motion-with attendantWear ofthe working parts. The machine of the present invenrtionis soarranged that it issimple in construction, and fast and smoothoperation. and it is peculiarly adapted for heat-sealingithe top flapsof filled cartons;although-some-pfthe novelfeatures thereof are equallyadapted to be usedthe cartons and through which heat isfirst transmitted to the top closure and then removed therefrom. A furtheroloject'i s' teprovideanovu and;

efici'e'nt collar; arrangement for holding the;- car tons duringthetop-se'aling operation. Still'ariot-h'r Object is to provide aneitlefiily s-ihrpl arrangement iorreinoving' sealed 6a foris f oni; thecarton pockets. Further objcts',advantages and u'ses'of the inventionv'vill'he apparent fioiii the following detailed description "of apresently preferred embodiment thereof, wvhioh'fsh d he read inconjunction with the drawin'gs'iformihga' part of thisspecifioation.

In the drawings':

showing the othenendbf the machine of Fig. 1

. andoonstituting 'a continuation of Fig. 1;

Fig. 1 1s-a s mpl1fieqv1ew1n elevation of'one" end-of a sealing machine'accordirig to the 15-" Fig. 2 shows in perspective the drivingmechanisms which actuate the various devices incorporated in that end ofthe machine illustrated in Fig. I;- l

Fig; 2--'A is a continuation of Fig; 2 showing the driving mechanismsassociated with the endof the machine illustratdin Fig. 1-5.;

Fig. 3 is a partial plan view of one of the duplicate carton-sealinglines with which the machine of Figs. 1 and 1'A is equipped,illustrating' particularly the carton entrance arrange ment, theoperation ofthe carton pockets and the flap-folding devices;

, Fig. 4 is an enlarged perspective view of the cartonentrance-mechanism in somewhatgreater detail; V v

Fig. 5 is an enlarged perspective view of the first carton flap-foldingmechanism;

Fig. 6' is an enlarged perspective View of the second of; theflap-folding mechanisms;

Fig. 7- ;shows-in perspective one of the carton pockets with its j-awmembers'open for thereception of a carton; V t

Fig. 8 shows the carton pocket of Fig. 7 in closed position; v

Fig. 9 is a fragmentary view showing the trip mechanism forsynchronizing" the entering car tons'w'ith' the continuously movingcarton pockta; p V FigfllO is ahothefviewofthe trip'mecnanism er Fig. 9answering the position of the parts the jcliiteli member is engagedFigs. 11,.1221111513 represent diagrammatically three s cce's'sive'stagesin the'folding of the end wall'flap;

Figs. 14, is than represent diagrammatically the side wallflapsfand V gv v Flg's.1'7, 18 and 19 represent cliagifammatically three suc'ces'sivstagesin-th'e' folding of the over-a three successive stages in thefoldingof one'of The particular embodiment of the invention illustratedin the drawings is a top-sealing machine provided with two separatecarton-sealing lines which are identical in construction and operation,but for the sake of brevity and simplicity, only one of these lines willbe completely described. Furthermore, it will be observed that thedrawings show little or no supporting structure such as frames,bearings, bearing supports, etc., since such structure is not essentialto an understanding of the invention and could be supplied readily byone skilled in the art.

Referring first to Figs. 1 and 1A, an endless chain 28 is arranged totravel over sprockets 2i and 22, so that its upper reach moves from leftto right, and it is provided at regularly spaced intervals with a seriesof carton pockets generally designated at 23. rangernents will bedescribed in detail below, Figs. 1 and 1-A indicate the relativepositions of the carton inlet mechanism 28, the end wall flapfoldingdiscs 25, the side wall folding devices 28 and 21, the endless belt 28traveling over pul- While each of these ar-' leys 29 and 38 and throughwhich heat is trans- I mitted to the carton tops from heating element3|, the endless belt 32 which travels on pulleys 33 and 34 and which iscooled by the cooling element 35, and the carton removal arrangementwhich comprises belt 38 traveling on pulley 31 and another pulley whichis not shown.

It is believed that the operation of theseparts can be explained moreimply if the driving mechanism which ac'tuates them and which have beenlargely omitted from Figs. 1 and 1--A, are first described, andreference is, therefore, made to Figs. 2 and 2-A. Due to the fact thatall of the movements of the various parts except belt 38 must besynchronized, they are all driven from a single prime mover, which isillustrated by way of example in Fig. 2A as electric motor 88 and whichdrives sprocket 41 through the speed-reducing unit 42. Sprocket ll inturn drives shaft 43 by means'of chain 44 and sprocket 45,,thus causinguniform continuous motion of the chains 28-which travel on sprockets 22mounted on shaft 48. At one end of shaft 43, sprocket 46 is providedwhich drives the tWo cold belts 32 substantially in synchronism withchains 28 by means of a linkage consisting of chain 4?, sprocket 48,shaft 48, gear 58, gear 5I, shaft 52, sprockets 53, chains 54, sprockets88 and shafts 88. The lower reach of each of the-belts 32 is locateddirectly above one of the chains'28 and the gear and sprocket ratios aresuch that belts 32 travel at the same or nearly the same linear velocityas chains 28. Hot belts 28 are similarly actuated from shaft 52 by meansof sprocket 51, chain 58, sprocket 58, shaft 68, sprockets 8 l chains62, sprockets 63, shafts 84 and pulleys 38, and they are alsosubstantially synchronized With'chains 28.

The remainder of the mechanism is actuated from shaft 85 (Fig. 2) uponwhich sprockets 2I are mounted and which is driven by the movement ofchains 28 over sprockets 2|. The flapfolding mechanisms 25, 28 and Hereall driven from shaft 88 which rotates at a speed bearing a definiteratio to that of shaft 65 since it is coupled thereto by means ofsprocket 61, chain 68 and sprocket 89. The rotation of end wallflap-folding discs is accomplished by means of chain I8 running oversprockets H, l2, l3 and 14 and the relative sizes of the Varioussprockets involved are chosen in this case so that discs 25 make twocomplete revolutions during the time required for chain 28 to travel adistance equal to the spacing between equivalent parts of adjacentcarton pockets 23. The reason for this will be discussed more fully whenthe folding operation is described. The side wall flap folders 28 and 27are actuated by two vertical shafts I5 and I8 upon which are mounted thecooperating gears TI and 18, so that they turn at an equal rate but inopposite directions, shaft 15 being in turn driven from shaft 88 bymeans of the cooperating bevel gears 19 and 88. It will be understoodthat another pair of side wall flap folders are similarly arranged anddriven from the other end of shaft 85.

The carton supply belts 8I which deliver the cartons to the duplicatemechanism for transferring cartons to the carton pockets 23 mounted oneach of the chains 28 are synchronized with the chains 28 and travelover pulleys 82 mounted on shaft 88 and another pair of pulleys whichare not shown. This drive runs from sprocket 84 on shaft 85 throughchain 85, sprockets 88 and 81 mounted on sleeve 88, and chain 89, tosprocket 98 on shaft 83. Sleeve 88 is arranged to rotate on butindependently of the shafts 9| and, since the latter are used to actuatethe mechanisms for pushalso capable of rotating independently of oneanother.

For the purposes of simplicity, the operation of the carton-supplyingmechanism will be described as to the particular carton-sealing lineappearing closer to the observer in the various drawings and it will beunderstood that like parts are provided to operate similarly inconnection with the other such line. Referring, therefore, to Fig. 2, itwill be seen that shaft 92 is driven from sleeve 88 by means of sprocket93, chain 94 and sprocket 95, and that shaft 92 in turn drives sprocket98 by means of chain 88a and sprocket 98b. Sprocket 98 is arranged torotate freely on shaft 9| and to actuate the adjacent portion 9'! of theclutch 98 as is best illustrated in Fig. 4. The other portion 98 of theclutch 98 is keyed to shaft 9| and the clutch mechanism is so arrangedthat portion 99 will be actuated by the driven portion 91 only when triparm I88 is released. In this way,

' pass by on continuous moving chain 28,it is necessary that twocondition exist at the same time in order that the mechanism actuated bydisc I8I be put into operation. The first of these is that a cartonshould be ready to be pushed to a position just above chain 28 so thatit can be picked up by an approaching sprocket 23. This condition isassured by causing trip arm I88 to be held unless there are a pluralityand in this instance, at least, five cartons awaiting further handling.This is best seen in Figs. 3 and 4, the former of which shows thecartons on belt BI and between guides I85 being held against furthermovement by rod I88 forming a part of the pushing mechanism. The last ofthese cartons bears tively fast, the spnocke Fr mFi e- 61 M 1 41 L .it wll e ttet causes the lomer gngl f Lever M 1,, u my.- etes at 1 .12). tem y .e we -rem an i .ee.e t 1M sieg ite iewerend Bee meet wit e hee smxtien um vW; W n-. enmeill en age tt'i'l? 1.90- t s .e. .euten the e ee, hat i l ng th enem ,oi flatten is, .st ffieeient, e e 1% re H and Leer m il e the. eiee ien shew Eie- .0 end w l not. Pn v n en.- e em ntthe .e utreh 231 pet enamel; artene are avai able. this. fll'liz llfimfipl w ll we: eltt eiuteh. ea rom be em n en esed en as. mating-themehi gdevieee .seeqnel een t em name that the. p ee h ng earten m lset2.3 s the nrepe sewe neletien te th newt 9f e ren entr n e is iti esne:b .eitp le Remin eee nto Fi s-'13 and W1 h eeen that telle 1 m.em.t..-. ee mise e J 5 3a w i teng ge th u'n t ltt met. H4 arm-me; e pe oi..Q -rten oeket; it e ne ee and eat is w l e u e red M1 to be. met ed tothei it. .lle eun n, the low r de H5. which...e .e.e .e pmie tin p. tamlite-Will :be ewtm way txem me H133 to th position hewn a, l9,, 1 4 eeeieit t ip It? and mowin Qwsm emf-1 1- and dis 1.9. to make a .eom'pl tnemm ton as p ieyj epsty deeeribe 8 lee a ,qenyeetiene t pe but it wi hesleeeribed b i fl .qem e t e wi h iee- 9 and ;10, Th :rin porti n 91whic is he h w wung t0 x veal ether por em at the .deviee. is .wi pte tot te en the lat rally e ten n eellar pent n 39a whi h is. mt t -witllmenti 9.19,. am. i is, as m yiq sly me iene etmeeted to and driven bysprocket 93. Portion 99 is a,rrangedto drive shait 9.1 by mean net ehownand it pmwieled wit a. spe ial k y M? whi h is ircellar in .e Qss: .i0nso thatit. may he Rotated.

about a is. 1111a coonenaztmgckeyw y- With n memb r 53- Ke H7 is ri i1ye-f 2s to tri m 118 whic eme ges fro m mbe .91 thn ugh sl t L. ee th tkey HM H e mte ed thr u h i 1. efi lele e trip-a H19 m ve Jee Ween thnee t ee shew ie- .9 nd .9- trip m! '95 i n tme t u et in thems tien shwn mi e, 9 b m ene'et e .e-.b; .e ri ejee.t Show. Tle iter n e .ke M eeet PQWPF} it ttteeetee ee ene mbe 51 .19 and petzlee b. ...e e te en e wthtneuiteb e ele 1m s ler porti n 5 1a and the per-t ar er.- nee sq t etthis ettuetiet Xle whe the, tr p .11 Zeel i ts a ewe eet iex tttewn i.lt i le eeeereet tit-let a We tri .e xn .109 e z eld by ettt e 1W I erle er J t ther w l ee-n9 e a emen tw e? the ke ne t ee 1'9 19 he i 9 endhe sha t 55! Wil emem tet e etyfie ever hen ee .t ve e 4 ans H15 e e swatwe it m tri em .99 teet lett r ae ltmeethe e itt he? i F g ti le a e thurg n .e the .-%PI met tenet me tioned fla te Pert e M wi l ,t lty mer eretn t e when ve ttie in re iiste ith h .elr eve '29 n t inter eyrtee ethe m b 75 i 'tme epneren a even .t ee e tlt p a- 539.1 releeeet th .eluw l net b en a e net e ex definite Q1. 2. .e .e e e eteeehee we the? thth t 5." w ll then bexetetec unt rt ti is ense s by at ee t sme e theexe e u em 1%. PE i -F he f e .thtt it is de i able t9 tw the e e tithat 9 tim ete re el t ably .stte te time than IFQE1.

e aeeee re 1 1 9.

e11it h to beemne e a ed and.

f a. flattened eer pts e 2- bel 8!. tee ei-nee .11 it 9 stee z t mze wth h tlqt n" e tt es he we Q$19e$i9fl0 e eey 2 e complete carton-pushingg qpiqp gag pg. ett eee the time t e e tqn peetset met 4 eee te le eneime ttet p ar w -e 2 t e et ma he thheee tee te'lee p s teil .e the meeheiem r tten r e tt s he rteee eeee eetye y and at the m te t mes Witneet to the p eiti n o ee te @eekete 2% ate beet eh n-in :F e-

A 9f er m elee i -ve 11 9 ith r tide q eleei 94 Ju t 0 .ee s a seem e twe s ed b he; & w t n k a 9 9 tl h eete e el 2 be e member 4 eewes te te tte .ee hewn- T et e ends .ei est a iteyl epeette t ethe itl e tlzemte a d me Ile y re et e .t time ehe t'ttt ed fi9 9 eeeee etee lathewen.- ett ee me en .ttle side 9? t e meehie e al ead been t tede w t-finee te e hem t -e e te -.ie ,ee tszel .59 met ee v ee W11 le steeer ati.A P1 919 25 i tt le e z eeue ee en ed I t e. d eet ie slepe sitn the e:tem eetitqn-me; metnbe 11 ttzelatter eevi e efi-eetreel e 5" e that w enthe cha n .29 and it-ember it puehes e rtee in wee .di ee i e. t e n xtmeek met 3 mete e i m m e fi 6 e n e ed, tmts e petit o whet'eueen bet.8" er. .ee thie ten wwersltmtil it r t ineel b .ee e ilt wh ch se arted .et 6- hi i n met en e hieve by m -1 .e e s ewe ted L 58 hich e re l'ne en R e new 5 .1. t e ups t. snrfeee r blee $.25 and at the Ott r t apivot e been .hg 1.3.9 on h HEP- ur a e i .d se NJ nee; the \et i e-mttenee tne e t- It -i lx fi app ieet teai th -fet tha Whenev r the e ten8 is: en age i h mann al ead .elese ihed, t m .5 w ll make t .ee pletere e t en end member .5 w .tm e ewer and aw y it m he path. t main. .6 ea tie trene e e. erten from belt 81 t e min d re t be t e axis o he n 2tiu e.is-s.tep he patte slid we e Pl e 3! an et Pttly & Pl t 131 nd pa tl20 strip .32 which separa ed therefrom by e pelling 43.3 .eufiieientiywide to t e 120st. t [4: 9t eaeh. ce m le t .33 to pass tnerethzou h.

Re rring new 9 igs. 7 and .6. each of the art n p qk te 2.5 a iets. f ar e leer ex.- e tdi g acro s .ehe n end. ri idly seeulted to one of theiinks, thereo as by weldin a pair .of; id reds! 3.5v xt ndin fe wa rdlytheneimom her..- min t ng, in a .ere s bar L35 and the upri htnoe H4mounted on bar I34 cglir-ying the mephanmm treee yin a d. rinn n martentear its upper ed e Re s L and .eress bar 316 .eo st tute the ttuetm menwhi h th ,e tqn rests. and bar 1. .6 has. a pair Q lu 13?. en. its low reu ia e paced. n tee ee t9 .reee -e a Qertiqn o .ehein 2.0 he ween themWhil lugs 31 are. net. .eeemted 319 hair; 2 1 the .serve the u pose ofpr y ntftn r atm movem n at he .fe werd o tie .e e n n. neatiet 3 -we.29 i t a e in a m ht ite and thus e hancin the .s ab z ity i cartonnswk t when fieldin pen tiens e e lee-rimmed 1 on theleen en theze n- Ba.3.6 fie substantia ly:

angst? longer than bar I34 so that it may enter the grooves I38 inguides I39 as shown in Figs, 3, 5, and 8. From Figs. 1 and 1-A, it willbe observed that guides I39 extend adjacent chain 20 throughout theentire upper reach of chain 20 between sprockets 2| and 22, and there isa similar pair of guides I40 extending along the lower reach of chain 20thereby preventing any sagging of the latter and keeping the cartonpockets 23 moving always in a straight line.

Referring again to Figs, 7 and 8, the cartongripping mechanism comprisesa cross bar I4I upon which are swingably mounted a pair of arms |42having inwardly extending portions I43 at their ends. Arms I42 togetherconstitute a pair of jaws of such dimensions as to enclose theparticular carton to be handled, and they, as well as bar I4I, havesecured to their inner surfaces a number of small plates I44 extendingabove the upper surface of arms I42 to a point just below the top edgesof the cartons to be enclosed thereby. Furthermore, these plates are ofsuch thickness that when the jaws are closed as shown in Fig. 8, theywill form a continuous collar which grips the carton firmly on all sidesand holds it square. Furthermore, those plates I44 coming in contactwith the carton side walls are provided with portions I45 in their uppercentral section which project slightly inwardly to cause a slight inwardbending of the carton walls sufiicient to prevent the flaps on thecarton end walls from passing below the horizontal plane when they arefolded. Also, it will be noted that members I4I, I42 and I43 constitutea shelf which is capable of receiving such small amounts of excessthermoplastic material as may be forced from the flap surfaces duringthe sealing operation to be described, so that this excess material doesnot remain on the cartons and render them unsightly, nor does it drip onthe various parts of the machine indiscriminately. Arms I42 are normallyurged in the open position shown in Fig. 7 by means of coil spring I46,but as soon as the pocket 23 has traveled past the carton entrancepoint, the arms are moved to closed position by the action of cams I4'Iacting on rollers I48 mounted on the lower outer end of arms I42. Thisis best illustrated in Figs. 3, 4 and 8. As shown in Figs. 1 and 1--A,cam elements I41 extend along the machine substantially parallel to thepath of chain 20 as the latter passes around sprocket 22 and as itreturns toward sprocket 2| up to a point near the latter. Consequently,each carton is firmly held in the carton pocket while the flapfolding,heating and cooling operations are being performed and then returnstoward the entrance end of the machine in upside-down position. Justbefore each pocket passes upwardly around sprocket 2|, the cams I41flare outwardly, thus causing arms I42 to assume an open position sothat the carton contained therein slides downwardly and rests upsidedown upon belt 36 for removal from the machine.

In order that the various features of the invention may be completelyunderstood, the operation of the embodiment thereof shown in thedrawings will be described with respect to a typical carton passingthrough it, and the details of such of these features as have notalready been mentioned will be given in connection with thisdescription. In this example, the cartons ar conventional tubularcartons of rectangular cross-section, which have been bottom-sealed andfilled with the desired product, and which have a top flap on each ofthe side walls coated with a thermoplastic composition. these flapsbeing adapted id be overlapped to form a top closure.

In starting up the machine at least one and preferably several cartonsare placed on belt 8| against rod I06 so as to assure the presence of acarton in the proper position to be transferred to an approaching cartonpocket whenever the trip mechanisms are displaced so as to release triparm I00 as shown in Fig. 3. Chain 20 and consequently belt 8| are thenstarted and a sue-- cession of such cartons are made to approach theentrance mechanism on belt 8| between guides I05. Normally at least fivecartons will be present or will accumulate on belt 8| so that roller I01and lever I08 will be displaced in a clock-wise direction, and lever IIIwill be held away from trip arm I00. As one of the carton pockets 23approaches the entrance station, its upright column I I4 will come incontact with roller 2 and lever 3 will be displaced in acounter-clockwise direction, thus causing lever II6 to release trip armI00. As previously described, this actuates carton-pushing member I25and the carton in contact with it is rapidly slid across plate 3| untilit lies directly in the path of the approaching carton pocket. Pushingmember I26 then returns to its original position and the next carton onbelt 8| which has been held back by the off-set portion I2'I movesforward sufficiently to come in contact with rod I05. In the meantime,carton pocket 23 continues its motion and the carton in its path ispicked up by it. Almost immediately rollers I48 come in contact withcams I41 so that the arms I42 are swung to closed position and thecarton is closely held in upright position by the plates The carton thusheld continues its travel until the'side wall flaps, that is, thosewhich lie parallel to the direction of motion come in contact with theguide rods I49. These rods are best shown in Fig. 5 and serve merely todisplace the side wall flaps slightly outwardly for a short time so thatthe other pair of flaps, herein called end wall flaps, may be foldedwithout possible interference from the side wall flaps. The end wallflap-folding mechanism is very simple and consists merely in a pair ofdiscs 25 which are mounted on shaft I50 and rotated by means of sprocket12 as previously described. Discs 25 are arranged so that at theirlowest point their peripheries are substantially in the same plane asthe top edges of the approaching carton and they are spaced apart adistance such that they come in contact with the approaching end wallflaps near their side edges. Each of the discs 25 is provided with acut-away portion or notch |5| in register with each other and the motionof discs 25 and chain 20 are so synchronized that the notches |5I faceupwardly when discs '25 first come in contact with the leading end wallflap I52. Fig. 11 shows diagrammatically the relative positions of thecarton and discs 25 shortly after the folding of flap I52 has begun, andit will be noted that this flap is smoothly and easily folded byprogressive beneath discs 25. As the movement of chain 20' and discs 25continues, notch I5 I' moves around and contacts the upper and outeredge of the trailing end wall flap I53, somewhat as shown in Fig. 12, sothat finally flap I53 is folded into the same plane as flap I52, asillustrated in Fig. 13. It is necessary, in order to achieve the resultjust described, that the circumferential speed of discs 25 be greaterthan the linear velocity of the carton and in this case the parts are sosynchronized that discs 25 make two revolu- Meme? iciprocating partswhatever.

Returning again to :E'ig.'5, a hold=down=bani53 is provided .whichretains flaps "I52 and t in :their folded conditionluntil thidewaltfianse an be :foldedloverrupon them and thishold-downbar 154-isheated by means of .an electrical heating unit! 55 for the purposeofpre-heatingthegfolded flaps and softening the thermoplastic -materialthereon, whichremovesanybeads or othenirregur larities in the materialand materially aids the final heatasealing operation; wThis preheatingstep is especially effectivebecauseiof the :fact that :fiaps -I 52 and(Iii-are prevented fromenteringthe carton itself by theslightdepressionof the carton walls previously described so that they arenecessarily heldin good contactwiththesheatedholddown-bar 154. r 1 Thecarton in the advancing carton pocket :is

then-aetedruponby the side wall flapjtoldingtdevicesZB and '21-whichact-successively to :fold :the side wall flaps designated I58 and 159 Anthat order. Asishown in Fig. 6 flap folderi 6. includes a member L5fiwhich is arranged ,to present-a straight edgeullill to flapql58 along.-a:linejust above the top score line ofits-associatedside wall and soto fold flap l 5;8-intolcontact withfiaps @1152 and l 53, as illustrateddiagrammatically in Figs. 1.4, and '16. This iolding, however, is.notdone by moving the folding mernber' I56 in ,a directionperpendicularto edge I60, but-by causing titztoiollow a circularpathsuch that edge I16ll.travelswith, as well as .toward and away fromthe carton. This rotaryrmotion is achieved by mounting-the foldingmember 15,6,upon a pairof-rods 1-6], which in turn are supported atoneend bya block i612 mounted on an eccentric pivot ,on the uppersurrecent-horizontal disc [53. Disc1c l63 is ,-.arranged torotateaboutgvertical shaft {I 54 and-the other lar discnot xshownadapted-to rotate upon charts :15 (l-fig. 2). :Si-nee-shaf-t ,15, ashasalready been shown, rotates inva counterclockwise ,direction, shaft i-64 willdo ;likewise 1 and the folding member iii-6 will trayel in a,circulartranslationalmanner; Also, this/motion is synchronizedwith-themotion of chain :Zll sothat .edg-eififlis caused toraimroach andto move w th the atio J as t carto pocket is in the properpositionwithrespect to it.

Foldingdevice 27- similarly includes ga member 155i -mounted.;on rods Iwhich inturnanfi-support-ed byblo ii. I 6.60 sc fiLandrhe a t t tat:With sha Sha t zfifl a d fifir t te at :"the same rate and inoppositetdirfictions-be cause. of the :inte-rmeshing ,gears 469 and 1!),and also because :rods 165 are similarly .supmflted at their o h endsupon a co esp ndin d sc mounted on sh t 15. t is: se; o cou se..foldi-ng member I51 approaches the carton girom the other side, butit.acts in the same manner "as shown in :Figs. 1'7; 18 and;19. Initle-position oaths nartsshow im 6 io di i e ce 25' is ab u -toccmmenc thfc di i ifiapififl: These de ice sir m ie n positive cld necac o endsofirods 1,5 l. aresimilarlyimounted onasimidue tothe.straight-lineaction ofithedolding-edges and t y a e; al cpt na .sm qth i o an bec useo th c r u ot on us d. 71 7M :iO i -F-EEF Q IIW L5 n :51 a cisc mride te ctr a heatin JJiL' ndIrI'L whic =75 ,cartonltopso that this material1110 serve toxprevent theaccumulationtofthermoplasticmaterialupon-them;and also to'preheat flaps |;5 8 -andl59,.so as toprevent cooling of the thermoplasticlmaterials on flaps I52and I53 which have. already beensoftenedas described.

The carton in "the advancing carton pocket is .thenready ,-for "theheat-sealing operation, and so-passesunder the lower reach of belt 28,which holds the top fiaps in their closed position. -Duringthetransition period these top flaps are l zent &closed ,bymeans of aseries of rollers I173 whichgbear upon the uppermost of them. In theparticular application of the invention being described,-the;top;fiapsare coated with a thermo- -p lazsti c material and inorder toheateseal-them, .it 'islnecessaryto apply ,heatand'pressure in adownwardldirection upon substantially the entire may softenand flow soas to seal all of the cracks and crevices between and v adjacent theflaps. It is, thereiore necessary that belt-28 shouldbe heated insomeway and in the present instance, belt -28 is of a material having ahigh heat conductivity through-which gheat passes from the electricalheating unit :31 to the top surface ofvthe carton, and the distancebetween pulleys 29 r-andiiil and the length of heating unit 3| is suchthat the d sired, fl v mflllnt of heat is transmitted to :the cartontops. Inthe presently preferred formof the invention, belt 28isanendless.steelbel-t and it is slightly wider than the cartonsbeing-sealed so-that the heat istransmitted as evenly as pos- Sible tothe carton, Heating vUn t 3| is also slightly wider than thecarton andit has asmooth l we i cia 129 1 wh ch belt ;28 d easil w th l ttlciri ofleven o sh ha suria is a s e vertica tha it exert -e defin teandsubstantial.pressure uponthecartons-travelll the u de Q a n nde Pulle0 an lea in b l ,2 8, the carton moves forward until the top r surfacethereo f co mes ,in contact with belt 3;; the a fla in h {meantime einhe d shied o i n by m an e o le 14- 'Whil t-Wmils h qisible t c e the-cte s t 'QQQ wh l holdingthe to-p fiapsclosed by any suitable arrangement th-is would result inan exceptionally and undesirably. longtop-sealing line, so that it is much preferred to cool the thermoplasticmaterial at the top of the carton more quick- .ly. In this instance,thereforabelt 32 isza-steel belt similar to belt 28 and a cooling unit55 is provided which hasa smootnllowervsur face upon which .belt 32slides easily. -Obviously the distancebetweennpulleys Stand 3.4 dependsto -a rcatsrtW 1 9 th nature of t w l n med um 1 .5 a d i eiri em 1 i clr l fii directly within unit 3'5, this distance can be qllite si i lent e fact whic mu always be ake nt ewcue is of omm nc at o t veQf-QlaiMBLS mQc hi wciildis cterm ne th time thctlee hrc iten r htin heae th cu h be 28am ceglcdthrqu be i W cn the carton s eases .nc eyfiti icomp e y c le nd the top' closure is effectively sealed.

' Since tam-traces [41 extend around sprockets lithe cartons remain intheir carton-pockets 23 and return substantially the entire length ofthe niaChine toward theentrance end but they are, of course, in upsidedown position. ,At; a point just short of sprocketcil, cam-tracks MP!flare outwardlyiso that arms c142 swing outwardl v-under the infl encedn ntendin -99mnlet vvs a cartcnf r leased t icreirqm .13.?1 at isarranged t traw mew a helew th cartons as they are released and slidedownwardly from the various carton pockets in succession and serves tocarry them in the same direction from'the machine. Belt 36 and pulley 31over which it travels, are not necessarily synchronized with chain 20,although they may be, but in this instance they are separately driven ata somewhat higher linear velocity so that the released cartons will besure to clear pockets 23 before the latter start their upward travelaround sprocket 2!. One of the great advantages of this carton outletarrangement is its simplicity, but another is the complete absence ofreciprocating or timed motions which may get out of order.

It will be seen from the above that a carton sealing machine, inaccordance with the invention, has been described which has many novelfeatures and which is more advantageous than the devices of the priorart for many purposes and especially for heat-sealing cartons whoseclosure flaps have been coated with a thermoplastic material. Obviouslymany modifications may be made by those skilled in the art in the lightof the above disclosure, but such modifications are intended to bewithin the scope of the present invention.

While the invention has been described in connection with a specificembodiment thereof, it is not desired to be limited thereto, but only bythe scope of the following claims.

We claim:

1. A carton sealing machine especially adapted for closing and topsealing a series of filled cartons having integral top flaps coated witha thermoplastic composition and adapted to be overlapped to form topclosures therefor, comprising an endless chain conveyor, means fordriving said conveyor continuously in a predetermined direction, aplurality of carton pocket means mounted on said conveyor at evenlyspaced intervals, each of said pocket means being adapted to receive acarton in upright position and to grip the same just below its topedges, means for inserting cartons into said pocket means as the latterpass a carton supply position, means for folding said top flaps to formcarton closures as said cartons travel in said pocket means, an endlessmetal belt mounted to travel with its lower reach in contact with theuppermost of said folded top flaps, means for driving said belt atapproximately the same speed as said chain conveyor, means for heatingthe lower reach of said belt and exerting downwardpressure thereonsufiiciently to cause said thermoplastic composition to flow into thecracks and crevices between and adjacent said flaps, a second endlessmetal belt mounted to travel with its lower reach in contact with thetops of the cartons emerging from contact with said first-mentionedbelt, means for driving said second belt at approximately the same speedas said chain conveyor, means for cooling the lower reach of said secondbelt and exerting downward pressure thereon, and means for removingscaled cartons from said pocket means.

2. A carton sealing machine according to claim 1 wherein said heatingmeans has a smooth metallic lower surface in direct contact with theupper surface of the lower reach of said firstmentioned belt throughouta substantial portion of the length thereof.

3. A carton sealing machine according to claim 1 wherein said heatingand cooling means have smooth metallic lower surfaces in direct contactwith the upper surfaces of the lower reach of said belt throughout asubstantial portion of their lengths, l

4. In a carton sealing'machine for closing a series of cartons'havingtheir closure flaps at at least one end thereof coated'with athermoplastic composition, the combination comprising a 'conveyoradapted to move continuously in a straight line, means mounted at spacedintervals on said conveyor adapted to receive and retain a plurality ofsaid cartons, means for folding one pair of end flaps on opposite sidewalls of each of said cartons successively to closed position while theyare moving on said 'conveyor, separate means movable over said cartonsfor folding the other pair of end flaps on each of said cartonssuccessively to closed position overlying said firstme ntioned'pair offiapsand overlapping each other while said cartons are moving on saidconveyor, means for heating said separate folding means to soften saidthermoplastic composition and means for exerting pressur upon saidfolded flaps.

' 5. The combination of claim 4 wherein said separate folding meansincludes a pair of folding members having smooth lower surfaces adaptedto come into contact successively with substantial areas of the uppervsurfaces of said upper pair of flaps.

6. In a carton sealing machine for closing a series of cartons havingclosure flaps at least at one end thereof adapted'to be overlapped toform a closure lying substantially in a single plane and having athermoplastic composition distributed between at least certain of saidflaps, said machine including a conveyor, pocket means on said conveyorfor receiving said cartons, means for gripping said cartons adjacenttheir respective closures andmean's'for folding said flaps to form saidclosure, the improvement which comprises belt means formed of'aheat-conducting material, means for causing a reach of said belt meansto move substantially in synchronism with said conveyor and in contactwith substantially the entire outer surfaces'of those of said flapsforming said closures, and means also in contact with said reach of saidbelt means for supplying sufficient heat and pressure thereto to causesaid thermoplastic material to flow into the cracks and crevices betweenand adjacent said flaps.

T. A carton sealing machine especially adapted for closing and topsealing a series of filled cartons having integral top flaps coated witha thermoplastic composition and adapted to be overlapped to form topclosures therefor, comprising an endless conveyor, means for drivingsaid conveyor continuously in a predetermined direction, a plurality ofcarton pocket means mounted on said conveyor at evenly spaced intervalseach adapted to receive a carton in upright position and to grip thesame just below its top edges, means for inserting cartons into saidpocket means as the latter pass a carton supply position, means forfolding said top flaps to form carton closures as said cartons travel onsaid conveyor, means for causing flow of said composition into spacesbetween and adjacent said flaps comprising a first endless beltmounted'to travel with its lower reach in contact with the uppermost ofsaid folded top flaps and heating means for said lower reach exertingdownward pressure thereon, means for causing sealing solidification ofsaid composition comprising a second endless belt mounted to travel withits lower reach'in contact with the tops of the cartons emerging fromcontact with said first belt and cooling means for the lower reach ofsaid second belt, means for driving said belts at approximately the samespeed as said conveyor, and means for removing sealed cartons from saidpocket means.

The following references are of file of this patent:

THOMAS F. CASS, JR, DOUGLAS KIRK. FRANCIS W. LANIGAN.

REFERENCES CITED UNITED STATES PATENTS Number Name Date Cormack July 14,1903 16 record in the 10 Number 14 Name Date Martin June 30, 1914Chapman May 25, 1915 Bracy Jan. 14, 1919 Johnson Oct. 23, 1923 SandbergOct. 25, 1927 Bergsteln Feb. 21, 1928 Barritt July 9, 1935 Chekian Sept.17, 1935 Stlcelber Aug. 4, 1936 Petskeyes Jan. 11, 1938 Flncke Apr. 19,1938 Flncke Nov. 21, 1939 Richard July 2, 1940 Lowey et a1 Dec. 16, 1941

